AET. 13 TEEMATODE PARASITES OF MAEINE MAMMALS — PRICE 33 



Family HETEROPHYIDAE Odhner, 1914 



Family diagnosis. — Small or very small forms, usually not exceed- 

 ing 2 mm in length. Anterior portion of body thinner, usually 

 more slender and more movable than the posterior portion. Surface 

 of body covered with small scalelike spines that become reduced 

 posteriorly and may disappear tovt^ard the posterior end of the body. 

 Intestinal ceca simple, usually extending to the posterior end of the 

 body. Genital pore in the immediate neighborhood of the aceta- 

 bulum; genital ducts usually open into a genital sinus, which may 

 be variously modified and contain a cirruslike body or gonotyl 

 (genital sucker). Acetabulum usually median in position, but may 

 be displaced to the right of the median line ; in some instances the 

 acetabulum may be joartially or completely atrophied and inclosed 

 in the genital sinus. Cirrus pouch absent. Seminal vesicle well de- 

 veloped, U or S shaped, the vas deferens surrounded proximally by 

 a mass of prostatic cells. Testes oval, globular, or slightly lobed, 

 near the posterior end of the body, side by side, or obliquely one in 

 front of the other. Ovary oval, globular or slightly lobed, pretes- 

 ticular, usually to the right of the median line. Seminal receptacle 

 and Laurer's canal present near the ovary, usually in relation with 

 its posterior border. Vitellaria, located mainly in the lateral fields, 

 may extend anteriorly to or beyond the genital aperture. Uterus 

 usually restricted to the intercecal field between the ovary and 

 genital pore, but may extend to posterior end of body {Galacto- 

 somum). Adults parasitic in the intestine of birds and mammals. 



Type genus. — Heterophyes Cobbold, 1866. 



KEY TO THE GENEEA OF HETEKOPHYIDAE OCCUERING IN MARINE MAMMALS 



1. Acetabulum absent; uterus extending to posterior end of body. 



Galactosomum (p. 39). 

 Acetabulum present ; uterus not extending caudally beyond an- 

 tei'ior border of testes 2. 



2. Acetabulum not contained in the genital sinus; seminal recep- 



tacle median and slightly preovarial ; vitellaria not extending 



to acetabulum Phocitrema (p. 38). 



Acetabulum contained in the genital sinus ; seminal receptacle 

 lateral and postovarial ; vitellaria extending cephalad of 

 acetabulum 3. 



3. Genital sinus large; genital ducts open into sinus caudad of 



acetabulum Cryptocoyle (p. 33). 



Genital sinus small ; genital ducts open into sinus cephalad of 



acetabulum Apophallus (p. 35). 



Genus CRYPTOCOTYLE Luhe, 1899 



Synonyms. — Tocotrem^ Looss, 1899, p. 585; Uallum Wigdor, 1918, 

 p. 254; Ciureana Skrjabin, 1923, p. 67. 

 118893—32 3 



